I mean, those teams can't do it though because the three you listed are all starting under 23. That's the whole point. Not a single one of those three is a perfectly constructed team that has no inefficiencies on the roster.
Colorado is spending $4 million a on Ryan Johansen coming off a 0.5 point-per-game season to be the second line center (a hole Colorado had last year, by the way, after it couldn't afford to bring back Kadri due to cap constraints). Colorado also just had to play waiver roulette just to fill the backup goaltending position.
I doubt many people here would be stoked to be paying nearly $5 million to a second-line center who barely cracked 0.5 points per game last season like Carolina is. Carolina also doesn't exactly have what anyone would call elite goaltending between Andersen and Raanta.
Dallas is paying $9,850,000 to a 31-year-old Tyler Seguin who has been a 50-point player for the past 2 seasons. Dallas is also paying $9,500,000 to a 34-year-old Jamie Benn who rode
wild and unsustainble individual and on-ice shooting percentages after years of excessively inefficient contract-to-production value.
Each one of those teams is close to the cap (some more than others) while not one of those teams is icing a 23-man roster to start the year.